Meeting the latter
goal will require infrastructure investments of about US$23 billion per
year, to improve water services for 1.5 billion more people (292,000
people per day) and access to safe sanitation for 2.2 billion additional
people (397,000 per day). Fewer than one in five countries are on track
for meeting this target. How do water, sanitation and hygiene affect health?

Water supply, sanitation and health are
closely related. Poor hygiene, inadequate quantities and quality of
drinking water, and lack of sanitation facilities cause millions of the
world's poorest people to die from preventable diseases each year. Women
and children are the main victims.

Water, sanitation and health are linked in
many ways:

contaminated water that is consumed may
result in water-borne diseases including viral hepatitis, typhoid,
cholera, dysentery and other diseases that cause diarrhea

without adequate quantities of water for
personal hygiene, skin and eye infections (trachoma) spread easily

water-based diseases and water-related
vector-borne diseases can result from water supply projects (including
dams and irrigation structures) that inadvertently provide habitats for
mosquitoes and snails that are intermediate hosts of parasites that
cause malaria, schistomsomisis, lymphatic filariasis, onchocerciasis and
Japanese encephalitis

drinking water supplies that contain
high amounts of certain chemicals (like arsenic and nitrates) can cause
serious disease.

Inadequate water, sanitation and hygiene
account for a large part of the burden of illness and death in developing
countries:

Approximately 4 billion cases of diarrhea per year cause 1.35 million deaths, most-1.2 million-children under the age of five, about 15% of all under 5 deaths in developing countries.

Diarrheal diseases account for 4.3% of the total global disease burden (62.5 million DALYs). An estimated 88% of this burden is attributable to unsafe drinking water supply, inadequate sanitation, and poor hygiene. These risk factors are second,
after malnutrition, in contributing to the global burden of disease.

intestinal worms infect about 10% of the
population of the developing world, and can lead to malnutrition, anemia
and retarded growth.

6 million people are blind from trachoma
and the population at risk is about 500 million

300 million people suffer from malaria

200 million people are infected with
schistosomiasis, 20 million of whom suffer severe consequences.

Water supply, sanitation and
hygiene are about more than health.

Saved
time, particularly for women and children, is a major benefit. Beneficiaries of
water and santiation projects in India reported these benefits: less
tension/conflict in homes and communities; community unity, self-esteem, women's
empowerment (less harassment) and improved school attendance (WaterAid 2001).

Effectiveness of water supply,
sanitation and hygiene interventions

Improved hygiene (hand washing)
and sanitation (latrines) have more
impact than drinking water quality on health outcomes, specifically reductions
in diarrhea, parasitic infections, morbidity and mortality, and increases in
child growth (Esrey et al 1991; Hutley et al 1997). Most endemic diarrhea is not
water-borne, but transmitted from person to person by poor hygiene practices, so
an increase in the quantity of water has a greater health impact than improved
water quality because it makes it possible (or at least more feasible) for
people to adopt safe hygiene behaviors (Esrey et al 1996).

Experience shows thatconstructing water supply and sanitation facilities is not enough to improve
health; sanitation and hygiene promotion must accompany the infrastructure
investmentsto realize their full
potential as a public health intervention. Changing hygiene behavior is complex.
Hygiene promotion is most successful when it targets a few behaviors with the
most potential for impact. Based on extensive research, WHO and UNICEF have
identified hand washing with soap (or ash or other aid) after stool disposal and
before preparing food; safe disposal of feces and use of latrines; and safe
weaning food preparation, water handling and storage as the key hygiene
behaviors. A recent review (Curtis) of all the available evidence suggests that handwashing with soap could reduce diarrhea incidence by 47% and save at least
one million lives per year. This is consistent with other studies which found
that 12 hand washing interventions in 9 countries achieved a median reduction in
diarrhea incidence of 35% (Hill, Kirkwood and Edmond, 2001). Many of the most
successful interventions provided soap to mothers, explained the oral-fecal
route for disease transmission, and asked mothers to wash their hands before
preparing food, and after defecation. There are fewer studies of results of
interventions to improve feces disposal, but Hill et al. found a median
reduction of diarrheal disease of 26% (9 studies, range 0-68%), a median
reductions in all-cause child mortality of 55% (6 studies, range 20-80%) and a
median reduction in mortality from diarrhea of 65% (3 studies, range 43-70%).

What can the public
health sector do?

The public health sector can do several things, in
collaboration with other sectors, to help ensure that investments in water
supply and sanitation result in greater health impact.
Public health promotion and education strategies are needed to change behaviors so as to
realize the health benefits of improved waster supplies. Programs to improve
hand washing behavior appear to be feasible and sustainable especially when they
incorporate traditional hygiene practices and beliefs. There is less experience
with interventions that focus on changing feces disposal behavior and the
results are mixed (Hill et al 2001). New, better approaches to behavior change
are being developed, including a recent project that has shown excellent results
through persuading the private sector (soap manufacturers and the media) to
transmit health information by advertising soap and its appropriate use to
prevent diarrhea (see The Story of a Successful Public-Private Partnership in
Central America: Handwashing for Diarrheal Disease Prevention, 2001). School health programsSchool health programs offer a
good entry point for improved water supply and sanitation facilities and for
community hygiene promotion.It is a realistic goal in most countries to ensure
that all schools have clean water and sanitation. This enables schools to
reinforce health and hygiene messages, ensure they translate into action, and
set an example to students and the community. This can lead to community demands
for similar facilities.

The inter-agency partnership for Focusing Resources
on Effective School Health (FRESH) aims to increase access to, and improve the
quality, of schools and child-friendly learning environments around the world.
Guidelines and tools are being developed to help design, implement, monitor and
evaluate school sanitation and hygiene components of school, health, and water
and sanitation projects.

Additional things the public health sector can do:

work with other agencies that plan, develop
and manage water resources and basic water and sanitation services to advocate
and promote these investments, and ensure that activities to promote hand
washing, safe disposal of feces and continuous use and cleanliness of
sanitation facilities are included;

work with the agency responsible for
monitoring water quality and sanitation to help ensure that this monitoring is
carried out;

provide other sectors with reliable data on
water associated diseases and effectiveness of interventions to facilitate
better decisions with respect to water and sanitation projects;

provide leadership for action in hygiene
education, including building coalitions with private sector agencies to
achieve better results;

design, implement, and monitor hygiene
education and promotion components of water supply and sanitation projects;

advocate for including water, sanitation and
hygiene interventions in poverty reduction strategies and plans.

Do's and Don'ts in promoting
hand washing and hygienic behaviors

DO assess
sanitation and hygiene beliefs and practices as the basis for planning, and
involve community members/beneficiaries in planning and implementing
interventions. Maximize the impact of hygiene promotion and education by using
participatory techniques, targeting women and children, and using women as
facilitators.

DO
identify practices to be changed, targeting the four most critical: hand washing
with soap (or ash or other aid) before food preparation and after dealing with
feces; latrine use and safe disposal of childrenfs feces; safe weaning food
preparation; and safe water handling and storage.

DO offer a
range of technology options (e.g., different kinds of latrines) and explain
associated costs, maintenance requirements, advantages and disadvantages. Public
funds are better spent on promotional campaigns and training/establishing
latrine artisan businesses than on subsidies for constructing latrines.

DO
incorporate programs to change hygiene practices in water supply, sanitation and
health projects. In order for water supply projects to achieve positive health
benefits, they need to include sanitation and hygiene components. Health sector
involvement can contribute to the success of water and sanitation projects.
Don't provide hardware (water pipes and latrines) without the software (hygiene
promotion) and community training and organization to sustain/maintain services.

DO include
education and information to increase community demand for improved sanitation
facilities.

Hill Z, B Kirkwood and K Edmond 2001, Family
and Community Practices that Promote Child Survival, Growth, and Development:
A review of the Evidence", Public Health Intervention Research Unit,
Department of Epidemiology & Population Health, London School of Hygiene